DEET, the most widely used commercial insect repellent, offers powerful protection from vectorborne illnesses such as malaria and dengue fever. But it is toxic in high concentrations, expensive, and short-lived. Soon there may be a better option. In May Vanderbilt University biologist Laurence Zwiebel announced that a compound called VUAA1 is not only 100,000 times as strong as DEET but also potentially cheaper and less harmful to humans.
The key to the improved repellent is its mode of action. DEET seems to work by inhibiting cells on an insect’s antennae, dulling its ability to locate prey. VUAA1, which Zwiebel discovered after screening 117,000 chemicals, stimulates a single receptor cell, called Orco. When triggered, Orco causes every type of odor cell to fire, overstimulating the bug’s olfaction system and disrupting its ability to sniff out humans—or anything else. “I’m hoping to repel bugs from crops, grain storage, and people,” Zwiebel says. “To have an impact across those aspects of human life would be extraordinary.”
